On Wed, 29 Jan 2003, Kim Brennan wrote:

> I believe what you do is put the pins 22" apart (and level). Tie one
> end of the string to one of the pins. Run the string over to the other
> pin, and adjust the length until the hanging section is 8" deep. Tie up
> the string at that point. The path that the string takes is a natural
> hyperbolic, I believe.

That'd be a caternary curve.  I don't know if they're hyperbolics or not.
I'm pretty sure there's a way to do it that involves the string being
tight.  I know you can do an ellipse that way, but I can't remember the
details.  Involves two pins and a loop of string, I think.

             _ _
  __ _ _   _| | |  | David M. Brodbeck (N8SRE)              Ypsilanti, MI
 / _` | | | | | |  +-----------------------------------------------------
| (_| | |_| | | | @ cyberspace.org
 \__, |\__,_|_|_| "To the optimist, the glass is half full.  To the
 |___/             pessimist, the glass is half empty.  To the engineer,
                   the glass is twice as big as it needs to be."